As with other contracts (car leases, cell phone contracts etc), you must keep your payments up to date to keep your house and avoid any foreclosure action by your bank or mortgage company.
However, if your mortgage comes up for renewal and you remain in Bankruptcy or under a Proposal, it has been our experience that your best bet is to renew your mortgage without causing a review of its terms or of your personal credit situation. Generally the banks/mortgage companies will simply send you a form to renew your mortgage without reviewing your current credit report if you have been in good standing and made your payments on time during the course of the mortgage term. As such, it is in your best interest generally to sign and renew where requested.
If you have to “re-qualify” for a new mortgage, it may be more difficult if you remain un-discharged from either a Bankruptcy or a Proposal.